As others have said, the best thing your son can do is run far from this deal, buckle down, save his pennies (he probably already is doing this), house-hack, and improve a property with sweat, hard work, developing a DIY skillset, and self-managing tenants. 

My tough today is different than my tough next week.Many new(er) investors struggle to manage their rentals well.

Try interviewing at least three managers.1.

I have two options 6.625% 30 year or 6.15% 15 yearI want to invest aggressively in the near future on more propertiesThe loan is only $110k and the monthly payment for 15 year is $563 and $750I will earn 2-3k a month in gross rental revenueThe property is in a declining population areaRecently rennovated, and all major things were relatively recently improved such as plumbing, the roof, a/c, electric, etc.Will require a lot of management as it is rent by the room so I may switch to a normal rental after 10 yearsI'm trying to find what will mathematically net me the most money in the long run.

SwissPMG can assist you in your property search, underwrite, acquisition, rehab and property management here in Columbus, OH.

Your project manager should know plenty of guys- delegate this to them3.

Do you put managers/assistants/employees in as co-hosts? 

If you have no facts, then yes an appraisal can be your ticket, but also keep in mind how your state manages assessed values.

With a larger organization like iintoo you'll likely be talking to an account manager that has been assigned to working with you.

I would also add, a contractor that you can buy materials for and they know how to put them in with little to know direction (reduces the management time of the project).